An optimal fleet-wide CO2 emission strategy for Ontario

Abstract

Large scale optimization of CO2 emission reduction from the Ontario power grid was studied. The problem was formulated as a mixed integer linear programme (MILP) and was implemented in GAMS (General Algebraic Modelling System) and was applied to the existing Ontario Power Generation (OPG) fleet. Two mitigation options were considered in this study: fuel balancing and fuel switching. The optimization results show that fuel balancing can contribute to the reduction of CO2 emissions by only 3%. Fuel balancing also results in a reduction of operating cost by 2.4% by reducing electricity generation from all four natural gas boilers by 32.1% and two coal fired boilers by 33.4% and 59.4%, respectively. The electricity generation from other fossil fuel boilers and non fossil fuel power plants were increased by 1% above the nominal operational level to maintain the electricity to the grid. However, if CO2 emissions are to be reduced beyond than 3% (e.g. 6% for Canada Kyoto Target), more stringent measures that include fuel switching and plant retrofitting will have to be employed. The optimization results show electricity generation from 3 natural gas boilers (LN1, LN2 and LN3) need to be reduced by 32.1%, one natural gas boiler (LN4) reduced by 8.2%, 2 coal fired boiler (LV1 and LV2) reduced by 59.4% and 34.8% respectively and the other coal fired boilers and non-fossil fuel power plants increase the electricity generation by 1% higher than the nominal operational level. Finally, 4 coal fired boilers (L1, A1, TB1, TB2) need to be switched to natural gas resulting in a cost increase of about 1.2%. For the case of a 20% reduction in CO2 emissions, nine coal boilers need to be switched to natural gas (compared to only four for the case of a 6% CO2 reduction).